Water heater



June 16, 1942. k GRETH 2,286,67 7

WATER HEATER Filed July 31, 1940 27 Z/ 14 .IIIVIIII l3 u 73 mm [Hue/77a- Patented June 16, 1942 UNiTED STTES ATENT OFFICE Claims.

This invention, a water heater, is an improvement over existing types ofwater heaters in that a more efiicient application and utilization ofthe heat is effected, thus increasing the overall efficiency. Itincreases the proportionate amount of heat transferred to the water fora given amount of fuel over that of the usual types of heaters. In thecase of tests conducted in comparison with some existent Water heaters,a heat absorbtion of as much as four times that of the other heaterstested, was indicated.

This high efficiency is created through the elimination of heatfunneling through the center of the coil; through the introduction ofmeans which directs all of the heat from the burner directly to andaround the coil; of eliminating the central funnel through the coil andequalizing the obstructional area of the coil with that of the heatpassage about the coil; and by flaring the heat from the burner directlyto the convolutions of the coil.

The objects of the invention are as follows:

First; to provide a water heater of maximum efficiency as related to theamount of water heated to a specific temperature on the basis of aspecific consumption of fuel.

Second; to provide a water heater in which funneling of heat iscompletely eliminated, and in which all heat created by the fuel isdirected into circulatory cooperation with the heating coil.

Third; to provide a water heater in which the obstructional area of thecoil to the travel of the heat is approximately equal to the freepassage for the heat about the coil.

Fourth; to provide a water heater with means for eliminating the centralfunneling area and which means coincidently functions as a director vofheat, to direct all heat from the burner into its most effective pathfor heating the coil.

Fifth; to provide a water heater in which the heating coil is secured inposition to the water jacket, at its opposite ends by means of compression couplings, so as to enable convenient removal and replacementof the coil.

Sixth; to provide means for eliminating the funneling of heat withcentering means for assuring centralization within the coil and thusassuring equalization of heat transfer throughout the height of thecoil.

Seventh; to provide means for eliminating the funneling of heat withadjusting means for adjusting the means relative to the burner.

In describing the invention, reference will be made to the accompanyingdrawing, in which:

Fig. 1 is a sectional elevation through the in- 7 in full View.

Fig. 2is a section taken on line 22 of Fig. 1.

The invention includes the drum l0 which may be either, a water tank, orthe water jacket of a side arm heater, and is suitably constructed withdome-shaped top and bottom H and i2 adapted to withstand predeterminedinternal pressures. A hot water outlet [3 communicates with the top IIof the water jacket, and a cold water inlet [4 extends down to a pointI5 close Y to the bottom l2 of the jacket.

A thermostat l6 projects into the water within the jacket and controlsthe operation of the burner i1, and a drain spout is provided at I8. Acylindrical-sleeve l9 extends throughout the height of the jacket and issuitably sealed and secured in the top H and bottom I2 of the jacket asindicated at 20. A suitable stove pipe reducer 21 is mounted at-theupper end of the sleeve l9 which is usually designated as a flue.

Mounted within this flue I9 is a heater coil 22 which extends from apoint 23 close to the top of the jacket where it is secured in place bymeans of the compression coupling 24, to a point 25adjacent the bottomwhere its other end is secured by another compression coupling 26.

Mounted within the convolutions of the coil is a fluecore 21 whichextends throughout the height of the heatercoil 22 and is preferably oftubular construction to form a dead air space 28 within the core andfunctions primarily to prevent funneling of heat upv through the centerof the coil, and secondarilyto transfer heat absorbed by this core,through radiation to the coil;

' the top end being preferably closed as indicated at 29 to preventcirculation of cooler gases within the core. The diameter of this coreis preferably made equal to approximately, the diameter of the flueminus four times the diameter of the tubing forming the coil.

The bottom endof the core is preferably of conical form as indicated at3B for deflecting all heat from the burner. directly to the spacebetween the core andthe flue walls as indicated by the flow arrows 3|,though this lower end might conceivably be of streamline or othersuitable form, though with a slight loss in efiiciency and a slightincrease in the cost of production. A flat or substantially flat end isnot so desirable since it would result in loss of efficiency throughconduction of a greater amount of heat upwardly through the core andwould forman obstruction to the free flow of heat. The inverted cone wasfound to be by far the most efficient.

Spacers 32 are provided at the upper and lower ends of the core andfunction to centralize the core within the coil, and also fortransferring heat from the core to the coil by conduction. Suitablemeans such as the projection 33 or rods 34 provides a support for thecore, the core being thus supported by the coil. The convolutions of thecoil function as threads, which in combination with the members 33 or 34form adjusting means for adjusting the core axially relative to theburner, and the.core is therefore removable and replaceable at will. Therods 34 when used, coincidently function as spacing devices forcentrally locating the .core in the flue, thus the combination ofspacers 32 and rods 34 will centralize the core in the coil and the coreand coil in the flue.

The heater coil is so constructed,proportioned and located that an eventransfer of heat is effected to the interior and exterior peripheries ofthe coil. To'illustrate: The core 2 'I transfers heat by radiation tothe interior periphery while the flue I 9 absorbs heat which ittransfers to the water in the jacket. Thus, 'if the area between theinner periphery of thecoiland the core, and that between the outerperiphery and the flue walls, were equal, the heating efficiency wouldsuffer, since the available heat within the coil would be excessive andheat would be lost through poor absorption, while the available heatbetween 'the coil and the flue would be lacking, and heat transferbetween the outer and inner peripheries would be out of balance.

For this reason the area between the outer periphery 'ofthe coil and theflue wall is made greater than that'between the inner periphery of thecoil and the core, slowing down the flow ofjheat between the coil andthe core relative tothat between the coil and the fluewall. Thus thehighest efficiency and most rapidand uniform heating of water isrealized.

Having regard to the foregoing disclosure, it will be understood thatvariations in construction and arrangement of'partsf'which variationsare consistent'with the appended claims may be resortedto withoutdetracting from the spirit or scope of the invention, or'sacriflcing anyof the advantages thereof.

.1 claim:

1. A water heater comprising; a water jacket having a'vertical flue ofuniform cross-section throughout its height andterminating at its upperend ina 'stove pipe reducer; a heater coil mounted in said'flue; aburner at the lower 'end of's'aid fiue; and a cylindrical core uniformin cross-section mounted within the confines of the convolutions of saidcoil and spaced from the inner peripheries of the'convolutions thereofand extending throughout the height of the coil and terminating innon-obstructive spaced relation below the lower end of s'aid'reducer andterminating at its lower end in an inverted cone and forming an annularflue for directing all heat from the burner to a limited area about theconvolutions of the coil and preventing funneling ofheat through theaxis of the coil and arms projecting laterally from said core andcooperating with the walls of the flue' for centering the core, andresting and adjustable on the convolutions, of the coil for adjustingthe tip of the cone vertically relative to the burner through manualrotation of the core.

2, A water heater comprising; a water jacket having a verticalcylindrical flue extending therethrough terminating at its upper end ina stove 75 pipe reducer; a burner located at the lower end of said flue;a heater coil axially mounted in said flue and removably secured incommunication with said water jacket at its opposite ends; a cylindricalcore of uniform cross-section axially supported in said coil andextending throughout the height thereof and terminating innonobstructive relation to said reducer for free escape of gases andhaving an inverted cone formed at its lower end with its point locatedin spaced relation to said burner; said core having spacer elements formaintaining the core in axial position relative to the coil, andsupporting means comprising arms laterally projecting from the core forcooperation with the convolutions of the coil and which arms have atransverse length equal to the inside diameter of the flue forcooperation with the walls thereof for maintaining the core axially inthe flue, and in combination with the spacer elements maintaining theflue, coil and core all in axial relation; said arms coincidentlyfunctioning as adjusting means for manual adjustment of the point of thecone relative to the burner through rotative cooperation with theconvolutions of the coil functioning as a thread.

3. A core for --a water heater having a heating coil, comprising; ahollow cylindrical-shell conically formed at its lower end and havingspacer lugs projectingradially from its upper and-lower end portions forcentering the core within the coil, and radial arms for supporting thecore on the convolutions of the coil and coincidentlyformingadjustingmeansfor axially adjusting the core within the coil'withthe-convolutions of the coil functioning as a thread.

4. A structure as defined in claim 3; said radial arms projectingbeyondthe outer periphery of the convolutions'of the coil-for centering I thecore and coil in saidwater heater, by cooperation with the inside of theheater.

5.-A Water'heater comprising; a'water jacket having an axial cylindricalflueof uniform crosssection extending vertically therethrough andterminating at its upperendina stove pipe reducer; a burner mounted atthe lower end of said flue; a heater'coil mounted axially in said flueand having its upper and lower ends in communication with said waterjacket; 'a'cylin drical -core uniform in cross-section axially mountedwithin saidcoil and terminating'at its lower end in an invertedcone'with thetip of the'cone in spaced relation to saidburner and withits upper end spaced-below in non-obstructive'relation to said reducerfor free flow of gases from said flue'throughsaid'reducer; said "coreconsisting of a hollow closed shell forminga'dead air spacewithinto-minirnize heat conduction and cause almost immediate radiationof the heat absorbed; spacers mounted on the upper and lowerportions'of'said core and projecting radially and cooperating with theinner periphcries of the 'convolutionsof said coil for uniform spacingof the core and coil;"and arins projecting from the upper and lower endsof sai'dcore and cooperating attheiri outer. ends with themside wall ofsaid'flue to space'the core and coil axially within said flue; said armshaving support on the convolutions of said coil and s'up-. porting thecore inspaced relation to said burner and functioning as adjusting"means for adjust-f ing the conical end of the-core relative to saidburner through manual rotation ofthe core, for maximum heatingefficiency.

AUGUST s. GRETH.

